Burglar alarm



NOV. 29, 19382 J A. W 2,138,316

BURGLAR ALARM I Original Filed Aug. 30, 1933 CLCSEBS m' ALL OPENINGS 3'9 57/7 3mm To'HousE LIGHTING 1 l/OMLnvE /g yvfih ggz C/raculT v Patented Nov. 29, 1938 UNITED STATES PATENT OFFICE August 30, 1933.

This application August 24,

1937, Serial No. 160,708

6 Claims.

This invention relates in general to electrical circuit closing devices and more particularly has reference to a burglar alarm system.

This application is a continuation of my application Serial Number 687,501, which was filed in the Patent Office August 30, 1933.

Previous to this time practically all of the available burglar alarm arrangements for actuating visual or audible indicators have required extensive alterations in the conventional wiring where it has een desired to install a device in an ordinary circuit. The prior systems have also usually been complex in construction and delicate in operation, so as not to be suitable for installation in a small dwelling or place of bus ness.

An object of this invention is to provide a burglar alarm which may be readily installed in an ordinary light circuit embodying a positive heavy duty circuit closing arrangement actuated to a simple relay.

Another object of this invention is to provide a burglar alarm device simple and compact in construction which may be economically produced and readily installed in an ordinary light circuit.

A further object of this invention is to provide a burglar alarm device which may be readily, positively and simply set in operative position.

A still further object of this invention is to provide a burglar alarm device which may be readily and permanently installed in an ordi nary light circuit and embodying an audible as well as a visual indicator, which will not interfere with the normal operation of the light circuit.

With these and other objects in view, which may be incident to my improvements, the in vention consists in the parts and combinations to be hereinafter set forth and claimed, with the understanding that the several necessary elements comprising my invention may be varied in construction, proportion and arrangement, without departing from the spirit and scope of the appended claims.

In order to make my invention more clearly understood I have shown in the accompanying drawings means for carrying the same into practical efiect without limiting the improvements in their useful applications to the particular constructions which, for the purpose of explanation, have been made the subject of illustration.

In the drawing forming a part of this specification, Fig. 1 is a side view of my burglar alarm device shown enclosed in a container, the elements set in inoperative position.

Fig. 2 is a side View of the device With the elements shown in operative position.

Fig. Sis a top View of the device taken on line 33 of Fig. 1.

Fig. 4; is a diagrammatic view of the device showing the relation of the elements in an electrical circuit.

Referrin more particularly by numerals to the drawings, in which the same and similar ele ments are designated by like symbols of reference throughout, and 'more especially to Fig. 1, my novel burglar alarm device comprises a single throw double pole switch embodying a base i and blades 2 and 3, as shown in Fig. 3. The blades 2 and 3 are pivoted at one end to cars 4 and 5 mounted on the base i and are adapted to selectively engage contacts 6 and l mounted on the other end of the base I. The base i or" the switch is angularly mounted on an arm 8 formed on the top of a bracket support 9. The bottom of the bracket 9 is formed with flange is for securing on an insulator base ll formed of any suitable non-conductive material, such as fiber. The insulator base it is adapted to fit in the bottom of a container I?! for enclosing the elements of the device.

An insulator bar it is connected across the ends of the switch blades 2 and 3 and a trigger I4 is centrally fixed on the outer face thereof in longitudinal alignment with the switch blades. The switch blades are normally adapted to be pulled in engagement with the contacts 6 and 1 by a helical spring l5 connected between thetrigger id and eye It fixed on the insulator base it, as shown in Fig. 2.

A pair of solenoid coils l1 and it are positioned opposite the switch, mounted on an upright l9 by an angle iron 20. The upright I9 is fixed on the insulator base H by angle irons 2i and 22. An armature 23 is adapted to engage the poles of the solenoids when the coils are energized. The armature is mounted in an up right position on a leaf spring E i fixed on the upright l9 by an angle iron 25. The armature 23 is normally held out of contact with the poles of the coils by the tension of the spring 24 and is adapted to be engaged at the top by the trigger M to hold the switch blades out of engagement with the contacts 6 and 1 against the tension of the helical spring l5. A stop 26 is fixed on the underside of the trigger Hi to position the armature with respect thereto. It will be apparent that with this arrangement of the switch and relay the blades will be released and pulled into engagement with the contacts 6 and l by the tension of the helical spring |5 when the solenoid coils are energized and the armature 23 engaged therewith to release the trigger M.

An upright 2? is also mounted on the insulator base ll between the switch and the solenoid coils. The upright 21 is formed with a flange 23 at the bottom for securing on the base, and a flange 29 at the top for extending over the trigger i and adapted to act as a stop therefor at its raised position. The bent leaf spring 30 is fixed on the flange 29 for engaging a blade 2 of the switch to complete an electrical circuit between that blade and the upright, as will later be described.

A wire 3| is connected at its lower end to the trigger M and extends through aligned apertures provided in the flange 29 and top of the casing l2 and formed with a loop 32 at the top to provide for setting the elements of the device in inoperative position from outside the container. When the switch blades are in engagement with the contacts, as shown in Fig. 2, so that the elements are in operative position, the device may be set by pulling the wire 3| from without the container to bring the armature 23 under the end of the trigger l4 against the stop 25 and the switch blade 2 into contact with the spring 35, where the trigger will be held until energization of the coils, which will withdraw the support of the armature and cause the switch blades to be snapped into engagement with the contacts 5 and l by the action of the spring |5. A pair of rivets 33 and 34 are affixed on the armature to engage the poles of the coils and prevent the armature from sticking.

The device is adapted to be interposed in an ordinary electric light circuit for actuating the lights and/or an audible alarm. The coils l1 and i8 may be energized by a dry battery or by transformer currents flowing through the light circuit. In Fig. 4 there is shown a diagrammatic view of the circuit for installing the device in which the numerals 35 and 36 indicate the positive and negative leads of an ordinary light current circuit. The transformer is shown connected across these leads comprising the usual primary and secondary coils 31 and 38 and a core 39. The numerals 40 and 4| indicate leads to conventional circuit closers at all openings, such as windows and doors, which are adapted to be connected in parallel in this circuit. The lead 4| is connected to a terminal comprising a post 42 and nut 43 mounted on the base. There is also connected to the post 42 a lead 44 to the coil H, which is connected to the coil is by a conductor 55. The coil i8 is connected to the upright 27 which is composed of conductive material by an insulated wire 45.

The other lead 40 to the circuit closers is connected to a binding post 41 which also has connected thereto a lead 48 from the transformer and a lead 49 to an audible indicator or bell 50. A switch 5| is interposed in the lead 49 for only selective actuation of the bell. A lead 52 is connected between the audible alarm and a binding post 53, which is also connected to the switch contact 6 by a lead 54. The blade 2 of the switch set in inoperative position is in contact with the leaf spring 36 fixed on the conductor upright 21. Another lead 55 from the transformer is connected to a binding post 56 to which there is also connected a lead 5'1 to the ear 4, on which the switch blade 2 is pivoted. The switch contact is connected by lead 58 to a binding post 59 to which there is also connected the line 36 of the light circuit. The ear 5 to which the switch blade 3 is pivoted is conected by a lead 60 to a binding post 5|, to which there is also connected one lead 52 from the house lighting current.

The operation of my novel burglar alarm device will be readily apparent from the foregoing description. The device is adapted to be interposed in a light circuit, as described, in series with the master switch in the circuit which is closed for operation of my device, and the light circuit open by setting of the trigger M on the armature 23 out of contact with the coils I1 and I8, as shown in Fig. l and in the manner described. Where use of the light circuit without operation of my novel device is desired the switch blades are allowed to be pulled in engagement with the contacts 6 and l, as shown in Fig. 2, and the switch 5| in the bell circuit is open so that the audible alarm will not be actuated.

When operation of my device is desired the trigger i4 is set, as shown in Fig. l, by raising the wire 3|. Whatever lights it may be desired to actuate with operation of the device are left in circuit with the lighting system. The switch 5| in the bell circuit is closed for actuation of the audible alarm, which may consist of a motor to actuate a siren. In the case of banks, a circuit closer, such as a button for being pressed by foot, may be employed. When any one of the circuit closers which are arranged in parallel are actuated, for example by the opening of a window or door to which the same are attached, the coils I! and I8 are energized by a circuit being closed through the lead 4| to 44, coil conductor 45, coil |8, lead 45, upright conductor 21, conductor spring 30, switch blade 2, leads 51, 55 and 40. The energization of the coils l1 and H3 will draw the armature 23 into contact with the cores thereof, releasing the trigger H which will be drawn downward under the tension of the spiral spring l5, opening the aforesaid circult by the switch blade 2 being drawn out of contact with the spring 30, and closing the bell and house lighting circuit to provide for visible and audible alarms by the switch blades 2 and 3 snapping into engagement with the contacts 6 and The bell circuit is thus closed through leads 52, 54, switch blade 2, leads 51, 55, 49 and switch 5|. The light circuit is thus closed to actuate the lights in the circuit through the leads 62, 55, switch blade 3 and leads 5!! and 36. If an audible alarm is not desired, switch 5| may be left open. The operation of the device may be discontinued by resetting through lifting of the wire 3| to bring the armature 23 under the trigger l4 and the switch blade 2 in contact with the spring 30, or by opening the master switch inthe lighting circuit.

There is accomplished by this invention a burglar alarm device simple in operation, compact in construction and economical of production for connection in an ordinary lighting circuit without substantial alteration thereof for use with or without a battery which will operate to afford a visible, or visible and audible, alarm by the closing of the circuit in which it is connected, such as by the opening of a door or window.

While I have shown and described the preferred embodiment of my invention, I wish it to be understood that I do not confine myself to 7 the precise details of construction herein set forth, by way of illustration, as it is apparent that many changes and variations may be made therein by those skilled in the art, without departing from the spirit of the invention, or exceeding the scope of the appended claims.

I claim:

1. In a switch construction, a casing, a pair of contact members mounted within the casing, a pair of blade members adapted to engage said contacts, a trigger movable with and in longitudinal alignment with said blades, a spring secured to the trigger and the base of the casing for normally urging the blade members into engagement with the contacts, a stop member mounted on the base of the casing for limiting the upward movement of the trigger, a spring contact mounted on the stop member for contacting one of the blade members, when the trigger is moved to its uppermost position, and

a spring supported element provided on the base of the casing for holding the blade members out of engagement with the contacts.

2. In a switch member, a casing, an angularly arranged support member, a pair of contacts carried by said support, a pair of blade members pivotally secured to said support and adapted to engage said contacts, a trigger movable with and in longitudinal aligmnent with said blades, a spring secured to the trigger and the base of the casing, for normally urging the blades into engagement with the contacts, a stop member mounted within the casing for limiting the up ward movement of the trigger, and a spring sup ported element provided on the base of the casing for contacting said trigger for holding the blade members out of engagement with the contactsv 3. In a switch member, a casing, an angularly arranged support member, a pair of contacts carried by said support, a pair of blade members pivotally secured to said support and adapted to engage said contacts, an insulating strap connecting the blade members, a trigger attached to the insulating strap, movable with, and in longitudinal alignment with said blades, a spring secured to the trigger and the base of the casing, for normally urging the blades into engagement with the contacts, a stop member mounted within the casing for limiting the upward movement of the trigger, and a spring supported element provided on the base of the casing for contacting said trigger for holding the blade members out of engagement with the contacts.

4. In a switch member, a casing, an angularly arranged support member, a pair of contacts carried by said support, a pair of blade members pivotally secured to said support and adapted to engage said contacts, a trigger movable with, and in longitudinal alignment with said blades, a spring secured to the trigger and the base of the casing for normally urging the blades into engagement with the contacts, a stop member mounted within the casing for limiting the upward movement of the trigger, a spring supported element provided on the base of the casing for contacting said trigger for holding the blade members out of engagement with the contacts, and a flexible member connected with the trigger and extending through the top of the casing, to move the trigger into contact with the spring supported element.

5. In a switch member, a casing, an angularly arranged support member, a pair of contacts carried by said support, a pair of blade members pivotally secured to said support and adapted to engage said contacts, an insulating strap connecting the blade members, a trigger attached to the insulating strap, movable with, and in longitudinal alignment with said blades, a spring secured to the trigger and the base of the casing, for normally urging the blades into engagement with the contacts, a stop member mounted within the casing for limiting the upward movement of the trigger, a spring supported element provided on the base of the cas-- ing for contacting said trigger for holding the blade members out of engagement with the contacts, and a flexible member connected with the trigger and extending through the top of the casing to move the trigger into contact with the spring supported element.

6. In a switch member, a casing, an angularly arranged support member, a pair of spring contacts carried by said support, a pair of blade members pivotally secured to said support, and adapted to engage said contacts, an insulating strap connecting the blade members, a trigger attached to the insulating strap, movable with, and in longitudinal alignment with said blades, a spring secured to the trigger and the base of the casing, for normally urging the blades into engagement with the contacts, a stop member mounted within the casing for limiting the upward movement of the trigger, a spring supported element provided on the base of the casing for contacting said trigger for holding the blade members out of engagement with the contacts, and a flexible member connected with the trigger and extending through the top of the casing to move the trigger into contact with the spring supported element.

JOHN A. WALL. 

